1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172
|
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/mman.h>
#include <linux/videodev2.h>
#include <libv4l2.h>
template <typename typeXX>
void clear_memmory(typeXX* x) {
memset(x, 0, sizeof(*x));
}
void xioctl(int cd, int request, void *arg){
int response;
do{
//ensures we get the correct response.
response = v4l2_ioctl(cd, request, arg);
}
while (response == -1 && ((errno == EINTR) || (errno == EAGAIN)));
if (response == -1) {
fprintf(stderr, "error %d, %s\n", errno, strerror(errno));
exit(EXIT_FAILURE);
}
}
struct LMSBBB_buffer{
void* start;
size_t length;
};
int main(){
const char* dev_name = "/dev/video0";
int width=1920;
int height=1080;
int fd = v4l2_open(dev_name, O_RDWR | O_NONBLOCK, 0);
struct v4l2_format format = {0};
format.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
format.fmt.pix.width = width;
format.fmt.pix.height = height;
format.fmt.pix.pixelformat = V4L2_PIX_FMT_RGB24;//V4L2_PIX_FMT_YUYV //V4L2_PIX_FMT_RGB24
format.fmt.pix.field = V4L2_FIELD_NONE; //V4L2_FIELD_NONE
xioctl(fd, VIDIOC_S_FMT, &format);
printf("Device initialized.\n");
///request buffers
struct v4l2_requestbuffers req = {0};
req.count = 2;
req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
req.memory = V4L2_MEMORY_MMAP;
xioctl(fd, VIDIOC_REQBUFS, &req);
printf("Buffers requested.\n");
///mapping buffers
struct v4l2_buffer buf;
LMSBBB_buffer* buffers;
unsigned int i;
buffers = (LMSBBB_buffer*) calloc(req.count, sizeof(*buffers));
for (i = 0; i < req.count; i++) {
clear_memmory(&(buf));
(buf).type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
(buf).memory = V4L2_MEMORY_MMAP;
(buf).index = i;
xioctl(fd, VIDIOC_QUERYBUF, &buf);
buffers[i].length = (buf).length;
printf("A buff has a len of: %i\n",buffers[i].length);
buffers[i].start = v4l2_mmap(NULL, (buf).length, PROT_READ | PROT_WRITE, MAP_SHARED,fd, (buf).m.offset);
if (MAP_FAILED == buffers[i].start) {
perror("Can not map the buffers.");
exit(EXIT_FAILURE);
}
}
printf("Buffers mapped.\n");
for (i = 0; i < req.count; i++) {
clear_memmory(&(buf));
(buf).type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
(buf).memory = V4L2_MEMORY_MMAP;
(buf).index = i;
ioctl(fd,VIDIOC_QBUF, &(buf));
}
enum v4l2_buf_type type;
type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
ioctl(fd,VIDIOC_STREAMON, &type);
printf("buffers queued and streaming.\n");
int pic_count=0;
///CAPTURE
fd_set fds;
struct timeval tv;
int r;
char out_name[256];
FILE* fout;
do {
FD_ZERO(&fds);
FD_SET(fd, &fds);
// Timeout.
tv.tv_sec = 2;
tv.tv_usec = 0;
r = select(fd + 1, &fds, NULL, NULL, &tv);
} while ((r == -1 && (errno = EINTR)));
if (r == -1) {
perror("select");
exit(EXIT_FAILURE);
}
clear_memmory(&(buf));
(buf).type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
(buf).memory = V4L2_MEMORY_MMAP;
xioctl(fd,VIDIOC_DQBUF, &(buf));
printf("Buff index: %i\n",(buf).index);
sprintf(out_name, "image%03d.ppm",pic_count);
fout = fopen(out_name, "w");
if (!fout) {
perror("Cannot open image");
exit(EXIT_FAILURE);
}
fprintf(fout, "P6\n%d %d 255\n",width, height);
fwrite(buffers[(buf).index].start, (buf).bytesused, 1, fout);
fclose(fout);
pic_count++;
clear_memmory(&(buf));
(buf).type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
(buf).memory = V4L2_MEMORY_MMAP;
xioctl(fd,VIDIOC_DQBUF, &(buf));
printf("Buff index: %i\n",(buf).index);
sprintf(out_name, "image%03d.ppm",pic_count);
fout = fopen(out_name, "w");
if (!fout) {
perror("Cannot open image");
exit(EXIT_FAILURE);
}
fprintf(fout, "P6\n%d %d 255\n",width, height);
fwrite(buffers[(buf).index].start, (buf).bytesused, 1, fout);
fclose(fout);
pic_count++;
///xioctl(fd,VIDIOC_QBUF, &(buf));
return 0;
}
|